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FrozenGate by Avery

Xenon flash tubes in series

About the coil, air core works, just "tie" all the loops together (it don't need to be elegant ;)) ..... about the diodes, they are there only for "turn off" the counterspike (how do you call it in English ?) from the coil itself, so they are in parallel with the coil, but connected in reverse of the working polarity (it's the same thing as when you place a diode in parallel of a rele coil, for avoid to burn the driving transistor when you turn it off and the coil "give back" the energy stored as a "counter-spike" ..... in this case, due to the low value of the coil, it's only matter of microseconds, so yes the diodes can last to this)

No images, sorry, my webcam is no longer working, after the last PC reformatting ..... the funny thing is that before it was working, and now the installation program say me to "upgrade windows to service pack 2" ..... and i'm already on SP3 :p :D ..... ah, well :p
 
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HIMNL9 said:
About the coil, air core works, just "tie" all the loops together (it don't need to be elegant ;)) ..... about the diodes, they are there only for "turn off" the counterspike (how do you call it in English ?) from the coil itself, so they are in parallel with the coil, but connected in reverse of the working polarity (it's the same thing as when you place a diode in parallel of a rele coil, for avoid to burn the driving transistor when you turn it off and the coil "give back" the energy stored as a "counter-spike" ..... in this case, due to the low value of the coil, it's only matter of microseconds, so yes the diodes can last to this)

No images, sorry, my webcam is no longer working, after the last PC reformatting ..... the funny thing is that before it was working, and now the installation program say me to "upgrade windows to service pack 2" ..... and i'm already on SP3 :p :D ..... ah, well :p
Click to expand...

ok i understood, thx.
No problem for the images. LoL yeah i know the problems related to webcams.. :|
i solved it installing win 7 :D

win xp is becoming a bit old XD

PS: the right word for the "counter spike" i think is "back EMF". It is a very big problem in the coilguns applications. i burned a cup of power diodedes lol
 
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I think there is a problem with voltage multiplier: the output current is very low at 50 Hz. If i link a relative big capacitor bank, with parallel balancing resistors, the VM goes in overload :(
 
Are you using a "ladder" multiplier ? (diode-capacitor ladder configuration) ..... or an external oscillator with a battery, like the ones in the disposable cameras ? (bigger, ofcourse)

For "ladder" multipliers, it's normal that the current is very low ..... you need to build an "inverter type" multiplier, with a high frequency oscillator (10 or 20 KHz ones are good choices, usually)
 
HIMNL9 said:
Are you using a "ladder" multiplier ? (diode-capacitor ladder configuration) ..... or an external oscillator with a battery, like the ones in the disposable cameras ? (bigger, ofcourse)

For "ladder" multipliers, it's normal that the current is very low ..... you need to build an "inverter type" multiplier, with a high frequency oscillator (10 or 20 KHz ones are good choices, usually)
Click to expand...

yes, the easiest way: 230 VAC 50 Hz --> cockcroft-walton --> 2500VDC
I should build an inverter 12-220VAC at high frequency combined with VM, or build a transformer 220 - 2500 V.... mmh
 
Ehm, a 220-2500V transformer is a bit "risky", you know (ZZZZZAPT :p :D) ..... but you don't need to build it, if you need it, any old neon-sign transformer for small signs can be ok (or you can probably get an used one from some signs companies for relatively cheap)

But if you want a portable unit, an inverter is the better choice ..... and, if you have enough skill in transformers building, is relatively easy to made one with already 2500V output (low current, but if is needed only for charge the capacitor bank in a relatively long time, it's ok)
 
Xenom said:
i have problem with parallel configuration: i tried with 8 tubes in parallel, one small capacitor, one hv trigger pulse.

Each time i trig, lamps flash randomly. I was not able to flash all lamps together and simultaneusly...
Click to expand...

This is to be expected: once a single lamp fires, it will drop the voltage across the whole arrangement under the ignition voltage for the other tubes, and the first tube to fire will dissipate all the energy you feed into the assembly.

Perhaps you may get lucky and get 2 or 3 lamps to fire at the same time if they are identical, but there is not guarantee of any kind this will work for every flash.

Wiring the lamps in series is much more reliable - they all need to trigger in order for the main capactor bank to discharge, and if it does, it does so equally between all lamps connected in series.

The downside is obviously you will need a higher voltage starting pulse to fire the lamps in the first place. Worst case this is 8x as high as for a single lamp when wiring 8 in series, though in practical application it will be lower... once a discharge channel is formed in one lamp, its essentially a short circuit that allows the next to fire - very much like xmas lights that short out when the filament fails.
 
HIMNL9 said:
Ehm, a 220-2500V transformer is a bit "risky", you know (ZZZZZAPT :p :D) ..... but you don't need to build it, if you need it, any old neon-sign transformer for small signs can be ok (or you can probably get an used one from some signs companies for relatively cheap)

But if you want a portable unit, an inverter is the better choice ..... and, if you have enough skill in transformers building, is relatively easy to made one with already 2500V output (low current, but if is needed only for charge the capacitor bank in a relatively long time, it's ok)
Click to expand...

all my project is a "bit" risky XD

Benm said:
This is to be expected: once a single lamp fires, it will drop the voltage across the whole arrangement under the ignition voltage for the other tubes, and the first tube to fire will dissipate all the energy you feed into the assembly.

Perhaps you may get lucky and get 2 or 3 lamps to fire at the same time if they are identical, but there is not guarantee of any kind this will work for every flash.

Wiring the lamps in series is much more reliable - they all need to trigger in order for the main capactor bank to discharge, and if it does, it does so equally between all lamps connected in series.

The downside is obviously you will need a higher voltage starting pulse to fire the lamps in the first place. Worst case this is 8x as high as for a single lamp when wiring 8 in series, though in practical application it will be lower... once a discharge channel is formed in one lamp, its essentially a short circuit that allows the next to fire - very much like xmas lights that short out when the filament fails.
Click to expand...

yes i tried the series configuration and it works. but now i have to improve capacitor bank and chargher system.

The difficult is to obtain 2500V at least with 5W of power...

anyone has a easy inverter circuit scheme working 12 to 220-300V + with high frequency?


i think is easier build a specific transformer 220-2500V... i can take one transformer and wire 10x the turns of primary.

is there risk of discharge on the secondary with normal magnet wire at 2-2.2 kV?
EDIT: WAIT! i need 2500 V DC so the RMS voltage must be around 1600 Vrms!
 
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Hehe... that sounds like overkill.

Also, you would have to limit the charge current so the lights actually turn off after they have fired. Powering the thing by a MOT would probably result in the lamps burning out because the arc is never broken and the transformer keeps feeding power until the flashlamps melt (and perhaps even after they do :D ).
 
Guys i tried today at half of the voltage; it seems to be working.
This is the configuration:
royer zero voltage switching inverter oscillator: 24 VDC IN, 240 VAC out at high frequency (200-500 kHz).
Voltage moltiplicator (capacitor-diode): 2 stage actually.
final voltage: 240*1.41*4 = around 1400 V.

capacitor bank: 9x 330 V 120 uF in series with balancing resistors. Total capacitance: near 10 uF, 3 kV max.

I tested the system with 4 xenon tubes in series supplied with 1400 V, 10 J.
Bright flash appears.

NEXT TRY: double the voltage and the tubes: 2500 V at 8 tubes, full power, around 40-50 J.
The flash should be 4 times powerful.

This is extremely dangerous lol.. i like it
 
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Ok people. NOW, i'll try the final test.
i have a little fear that something explodes lol.
 
IT WORKS! the flash is very bright and powerful. But i have to improve it because i noticed a bad smell.. i think some component is not well sized...

50 Joule disharged in 1-5 microseconds! 10 to 50 kW of istant light power!
 
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